Merge pull request gzc426#339 from heyheyheyi/master

gzc426 · web-flow · commit ad218f7d3ac3 · 2018-12-06T21:48:57.000+08:00
1
diff --git a/2018.12.05-leetcode102/棕榈树.md b/2018.12.05-leetcode102/棕榈树.md
@@ -0,0 +1,44 @@
+```
+public class levelOrderInBinaryTree {
+	public class TreeNode{
+		int value;
+		TreeNode left;
+		TreeNode right;
+		public TreeNode(int value) {
+			this.value = value;
+		}
+	}
+	
+	public List<List<Integer>> levelOrder(TreeNode root){
+		List<List<Integer>> list = new ArrayList<>();//存放一棵树
+		List<Integer> tempList = new ArrayList<>();//存放一层的值
+		if(root == null){
+			return list;
+		}
+		Queue<TreeNode> queue = new LinkedList<>();
+		queue.add(root);
+		int toBePrint = 1;//当前层要打印的节点数
+		int nextLevelCount = 0;//下一层要打印的节点数
+		while(queue.isEmpty() == false){
+			TreeNode temp = queue.poll();
+			tempList.add(temp.value);
+			toBePrint--;
+			if(temp.left!=null){
+				queue.add(temp.left);
+				nextLevelCount++;
+			}
+			if(temp.right!=null){
+				queue.add(temp.right);
+				nextLevelCount++;
+			}
+			if(toBePrint==0){ //打印完本层的节点，做善后工作
+				list.add(new ArrayList<>(tempList));
+				tempList.clear();
+				toBePrint = nextLevelCount;
+				nextLevelCount=0;
+			}
+		}
+		return list;
+	}
+}	
+```
